A radio-frequency permeameter

A transient-flow syringe air permeameter

In response to the need to better describe spatial variations in permeability, we designed and built a new portable field air permeameter for use on rocks in outcrop and core. In this instrument, a chamber containing a small volume of air in contact with the rock is suddenly increased in volume creating a vacuum, causing air to flow from the rock into the chamber. The instantaneous chamber volu...

The Viability of Oil Extraction from Trinidad Tar Sands by Radio Frequency Heating: A Simulation Approach

Trinidad has tar sand resources of about 2 billion barrels of oil on land in the Parrylands/Guapo and Brighton areas. With an oil price of over USD 25 per barrel, the commercial extraction of oil from Trinidad tar sands is viable, but it requires a careful study. The relatively small extent of this tar sand (about 10,000 acres and with depths varying from surface to less than 500 feet) and with...

Radio Frequency Interference Mitigation in Radio Astronomy

A Radio Frequency Bandpass ΣΔ A / D

1 Direct conversion of a radio signal into digital representation is highly desired. Such a system would allow all radio signal processing to be done completely in the digital domain. This is beneficial for many reasons. First, it allows for an RF system to take full advantage of the availability of inexpensive digital computation brought by modern digital CMOS processes. Second, computation in...

Radio Frequency Pulse Compression*

High gradients require high peak powers. One possible way to generate high peak powers is to generate a relatively long pulse at a relatively low power and compress it into a shorter pulse with higher peak power. It is possible to compress before DC to RF conversion as is done for the relativistic klystron or after DC to RF conversion as is done with SLED. In this note only radio frequency puls...